Update README

[ma-za-kpe]

After cloning the app, I get flutter: No file or variants found for asset: .env.

It would be much clearer to have docs say clone the repo and create a .env file at the root. Also, include the keys to have.

[damilola-paystack]

Hey @ma-za-kpe thanks for bringing this up. We'll make the update. Alternatively, you could also open a PR to help fine-tune the ReadMe based on your experience setting up the project.